A Canadian woman (Shona Holmes) with a tale of dangerously delayed brain surgery is back in the fray of U.S. politics, starring in a $6.3-million, anti-Democrat ad campaign that aims to show the perils of government involvement in health care just weeks before the American election… The resident of Waterdown, Ont., west of Toronto, sought out diagnosis and surgery for a non-cancerous brain growth in 2005 at the Mayo Clinic in Arizona, after facing a wait to see specialists in Canada that she believed could leave her blind, or dead.